Vacuum ultraviolet circular dichroism (VUCD) measurements will be made on beta-forming peptides, cyclopropane carboxylic acid derivatives, chitin, and chondroitin. The aim of the peptide measurements is to test the relability and predictive power of a model derived earlier for beta sheet formation in which the type of sheet, i.e., parallel or antiparallel, is determined by steric interactions between side chains. The objective of the remaining experiments is to establish the relationship between the conformation and optical properties of glycosylaminoglycans, through studies of (a) a carboxylic acid group attached to the rigid framework of a cyclopropane ring, (b) an array of acetamido groups attached to a polysaccharide backbone lacking uronic acid constituents (i.e., chitin), and (c) chondroitin, a glycosylaminoglycan having the same uronic acid moiety as hyaluronic acid, previously studied, but differing in the acetamido moiety (i.e., galactosamine instead of glucosamine). This selection of compounds thus represents a carefully chosen set designed to move forward our understanding of three aspects of glycosylaminoglycan optical properties and conformation: properties of an isolated uronic acid, properties of an array of acetamido groups, and an alternating array of uronic acid moieties and acetamido sugars related to a similar material previously studied, hyaluronic acid.